Granular composite(GC)hydrogels have attracted considerable interest in biomedical applications due to their versatile printability and exceptional mechanical properties.However,the lack of comprehensive design guidel...Granular composite(GC)hydrogels have attracted considerable interest in biomedical applications due to their versatile printability and exceptional mechanical properties.However,the lack of comprehensive design guidelines has limited their optimal engineering,as the factors influencing their mechanical performance and printability remain largely unexamined.In this study,we developed GC hydrogels by integrating microgels with interstitial matrices of photocrosslinkable gelatin methacrylate(GelMA).We utilized confocal microscopy and nanoindentation analyses to investigate the spatial distribution and mechanical behavior of these hydrogels.Our findings indicate that the mechanical and rheological properties of GC hydrogels can be precisely tailored by adjusting the volume fraction and size of the microgels.Furthermore,hydrogen bonds were identified as significant contributors to compressive performance,although they had minimal effect on cyclic mechanical behavior.Compared to bulk GelMA hydrogels,GC hydrogels demonstrated enhanced printability and remarkable superelasticity.As a proof of concept,we illustrated their dual printability in embedded printing to create prosthetic liver models for preoperative planning.This study provides valuable insights into the design and optimization of GC hydrogels for advanced biomedical applications.展开更多
Water can be used as oxidant in conjunction with metal particles to form metal-water propellant to increase the energy of propellant.For this application,water needs to be stored in form of solid and capable of becomi...Water can be used as oxidant in conjunction with metal particles to form metal-water propellant to increase the energy of propellant.For this application,water needs to be stored in form of solid and capable of becoming liquid when use.Stable and thixotropic hydrogel has good potential as water-retaining material and oxidant of metal-based propellant.In this study,we prepared organic/inorganic composite hydrogels by combining inorganic gellants hectorite and fumed silica with organic gellant agarose,respectively.The total content of the gellants can be reduced to less than 2%by adding agarose.The influence of agarose on water content,phase transition temperature,centrifugal stability and other basic physical properties of composite hydrogels were discussed.The results show that the composite hydrogels have better thixotropy and stability than pure inorganic hydrogels,and the gel-sol transformation can be realized by applying shear force or heating to the phase transition temperature.The composite hydrogels have good shear thinning ability and improved mechanical stability.Fumed silica/agarose hydrogels have better physical stability,while the thixotropy and shear thinning ability of hectorite/agarose hydrogels are better.展开更多
Growing health awareness triggers the public's concern about health problems. People want a timely and comprehensive picture of their condition without frequent trips to the hospital for costly and cumbersome gene...Growing health awareness triggers the public's concern about health problems. People want a timely and comprehensive picture of their condition without frequent trips to the hospital for costly and cumbersome general check-ups. The wearable technique provides a continuous measurement method for health monitoring by tracking a person's physiological data and analyzing it locally or remotely.During the health monitoring process,different kinds of sensors convert physiological signals into electrical or optical signals that can be recorded and transmitted, consequently playing a crucial role in wearable techniques. Wearable application scenarios usually require sensors to possess excellent flexibility and stretchability. Thus, designing flexible and stretchable sensors with reliable performance is the key to wearable technology. Smart composite hydrogels, which have tunable electrical properties, mechanical properties, biocompatibility, and multi-stimulus sensitivity, are one of the best sensitive materials for wearable health monitoring. This review summarizes the common synthetic and performance optimization strategies of smart composite hydrogels and focuses on the current application of smart composite hydrogels in the field of wearable health monitoring.展开更多
Wound healing in cases of excessive inflammation poses a significant challenge due to compromised neovascularization.Here,we propose a multi-functional composite hydrogel engineered to overcome such conditions through...Wound healing in cases of excessive inflammation poses a significant challenge due to compromised neovascularization.Here,we propose a multi-functional composite hydrogel engineered to overcome such conditions through recruitment and activation of macrophages with adapted degradation of the hydrogel.The composite hydrogel(G-TSrP)is created by combining gelatin methacryloyl(GelMA)and nanoparticles(TSrP)composed of tannic acid(TA)and Sr^(2+).These nanoparticles are prepared using a one-step mineralization process assisted by metal-phenolic network formation.G-TSrP exhibits the ability to eliminate reactive oxygen species and direct polarization of macrophages toward M2 phenotype.It has been observed that the liberation of TA and Sr^(2+)from G-TSrP actively facilitate the recruitment and up-regulation of the expression of extracellular matrix remodeling genes of macrophages,and thereby,coordinate in vivo adapted degradation of the G-TSrP.Most significantly,G-TSrP accelerates angiogenesis despite the TA’s inhibitory properties,which are counteracted by the released Sr^(2+).Moreover,G-TSrP enhances wound closure under inflammation and promotes normal tissue formation with strong vessel growth.Genetic analysis confirms macrophage-mediated wound healing by the composite hydrogel.Collectively,these findings pave the way for the development of biomaterials that promote wound healing by creating regenerative environment.展开更多
Three-dimensional graphene materials have been studied as typical supercapacitors electrode materials by virtue of their ultrahigh specific surface area and good ion transport capacity.However,improvement of the poor ...Three-dimensional graphene materials have been studied as typical supercapacitors electrode materials by virtue of their ultrahigh specific surface area and good ion transport capacity.However,improvement of the poor volumetric electrochemical performance of these graphene materials has been required although they have high gravimetric energy density.In this work,nanocellulose/nitrogen and fluorine co-doped graphene composite hydrogels(NC-NFGHs)were prepared through a convenient hydrothermal approach utilizing ammonium fluoride as the heteroatom source.Nanocellulose(NC)and high concentration of graphene oxide(GO)were utilized to adjust the structure of NC-NFGHs and increase their packing density.Subsequently,the aqueous symmetric supercapacitor based on NC-NFGH-80 exhibits remarkable gravimetric(286.6 F·g^(-1))and volumetric(421.3 F·cm^(-3))specific capacitance at 0.3 A·g^(-1),good rate performance,and remarkable cycle stability up to 10,000 cycles.Besides,the all-solid-state flexible symmetric supercapacitors(ASSC)fabricated by NC-NFGH-80 also delivered a large specific capacitance of 117.1 F·g^(-1)at 0.3 A·g^(-1)and long service life over 10,000 cycles at 10 A·g^(-1).This compact porous structure and heteroatom co-doped graphene material supply a favorable strategy for high-performance supercapacitors.展开更多
The ability to create artificial thick tissues is a major tissue engineering problem, requiring the formation of a suitable vascular supply. In this work we examined the ability of inducing angiogenesis in a bioactive...The ability to create artificial thick tissues is a major tissue engineering problem, requiring the formation of a suitable vascular supply. In this work we examined the ability of inducing angiogenesis in a bioactive hydrogel. GYIGSRG （NH2-Gly-Tyr-Ile- Gly-Ser-Arg-Gly-COOH, GG） has been conjugated to sodium alginate （ALG） to synthesize a biological active biomaterial ALG-GG. The product was characterized by IH NMR, FT-IR and elemental analysis. A series of CaCO3/ALG-GG composite hydrogels were prepared by crosslinking ALG-GG with D-glucono-8-1actone/calcium carbonate （GDL/CaCO3） in different molar ratios. The mechanical strength and swelling ratio of the composite hydrogels were studied. The results revealed that both of them can be regulated under different preparation conditions. Then, CaCO3/ALG-GG composite hydrogel was im- planted in vivo to study the ability to induce angiogenesis. The results demonstrated that ALG-GG composited hydrogel can induce angiogenesis significantly compared with non-modified ALG group, and it may be valuable in the development of thick tissue engineering scaffold.展开更多
In this study, the effect of silica/calcium phosphate (SiCaP) nanocomposite particles on the properties of a novel chitosan-based thermosensitive hydrogel system was examined. SiCaP nanocomposite powder was fabricated...In this study, the effect of silica/calcium phosphate (SiCaP) nanocomposite particles on the properties of a novel chitosan-based thermosensitive hydrogel system was examined. SiCaP nanocomposite powder was fabricated using a sol-gel method and then used to fabricate nanocomposite hydrogels (Ch- <em>β</em>/7.5SiCaP and Ch-<em>β</em>/15SiCaP) including chitosan and <em>β</em>-glycerophosphate (Ch-<em>β</em>) as a matrix. Results revealed that compared to the Ch-<em>β </em>hydrogel without SiCaP, the presence of SiCaP particles in nanocomposite hydrogels maintained pH stability during the sol-gel transition, accelerated the gelation and improved the stiffness of nanocomposite hydrogels. Gelation time at 37℃ was reduced approximately 75% and stiffness was increased approximately 115%. Both of these changes are attributed to chemical and physical interactions of the SiCaP bioactive particles with chitosan. Furthermore, compared to the Ch-<em>β</em> hydrogel, the presence of SiCaP in the Ch-<em>β</em>/7.5SiCaP nanocomposite hydrogel did not affect biocompatibility negatively, but improved osteoblastic cell differentiation. Our studies suggest that these nanocomposite hydrogels may offer an innovative approach to bone regeneration strategies.展开更多
Corresponding author’s name was incorrectly written as“Dadang Guo”instead of“Dagang Guo”.The correct author name should be“Dagang Guo”.The authors would like to apologise for any inconvenience caused.
Dental pulp-dentin complex defects remain a major unresolved problem in oral medicines.Clinical therapeutic methods including root canal therapy and vital pulp therapy are both considered as conservative strategies,wh...Dental pulp-dentin complex defects remain a major unresolved problem in oral medicines.Clinical therapeutic methods including root canal therapy and vital pulp therapy are both considered as conservative strategies,which are incapable of repairing the pulpdentin complex defects.Although biomaterial-based strategies show remarkable progress in antibacterial,anti-inflammatory,and pulp regeneration,the important modulatory effects of nerves within pulp cavity have been greatly overlooked,making it challenging to achieve functional pulp-dentin complex regeneration.In this study,we propose an injectable bioceramicscontaining composite hydrogel in combination of Li-Ca-Si(LCS)bioceramics and gelatin methacrylate matrix with photocrosslinking properties.Due to the sustained release of bioactive Li,Ca and Si ions from LCS,the composite hydrogels possess multiple functions of promoting the neurogenic differentiation of Schwann cells,odontogenic differentiation of dental pulp stem cells,and neurogenesis-odontogenesis couples in vitro.In addition,the in vivo results showed that LCS-containing composite hydrogel can significantly promote the pulp-dentin complex repair.More importantly,LCS bioceramics-containing composite hydrogel can induce the growth of nerve fibers,leading to the re-innervation of pulp tissues.Taken together,the study suggests that LCS bioceramics can induce the innervation of pulp-dentin complex repair,offering a referable strategy of designing multifunctional filling materials for functional periodontal tissue regeneration.展开更多
Meniscal injury,a prevalent and challenging medical condition,is characterized by poor self-healing potential and a complex microenvironment.Tissue engineering scaffolds,particularly those made of silk fibroin(SF)/hya...Meniscal injury,a prevalent and challenging medical condition,is characterized by poor self-healing potential and a complex microenvironment.Tissue engineering scaffolds,particularly those made of silk fibroin(SF)/hyaluronic acid methacryloyl(HAMA)and encapsulating Mg^(2+),are promising options for meniscal repair.However,the inflammatory response following implantation is a significant concern.In this study,we prepared a composite SF/HAMA-Mg hydrogel scaffold,evaluated its physical and chemical properties,and detected its fibrochondrogenic differentiation effect in vitro and the healing effect in a rabbit meniscus defect model in vivo.Our results showed that the scaffold differentiates pro-inflammatory M1 macrophages into anti-inflammatory M2 macrophages after implantation,thereby reducing inflammation and facilitating the growth and repair of meniscus tissue.Further,the composite scaffold provided a conducive milieu for cell proliferation,anticipatory differentiation,and generation of extracellular matrix.In summary,composite SF/HAMA-Mg scaffolds exhibit exceptional biocompatibility and anti-inflammatory properties,demonstrating superior potential for meniscal repair.展开更多
Designing advanced hydrogels with controlled mechanical properties,drug delivery manner and multifunctional properties will be beneficial for biomedical applications.However,the further development of hydrogel is limi...Designing advanced hydrogels with controlled mechanical properties,drug delivery manner and multifunctional properties will be beneficial for biomedical applications.However,the further development of hydrogel is limited due to its poor mechanical property and structural diversity.Hydrogels combined with polymeric micelles to obtain micelle-hydrogel composites have been designed for synergistic enhancement of each original properties.Incorporation polymeric micelles into hydrogel networks can not only enhance the mechanical property of hydrogel,but also expand the functionality of hydrogel.Recent advances in polymeric micelle-hydrogel composites are herein reviewed with a focus on three typical micelle incorporation methods.In this review,we will also highlight some emerging biomedical applications in developing micelle-hydrogel composite with multiple functionalities.In addition,further development and application prospects of the micelle-hydrogels composites have also been addressed.展开更多
A series of chitosan-g-poly （acrylic acid）/vermiculite hydrogel composites were synthesized and used as adsorbents for the investigation of the effect of process parameters such as vermiculite content, pH of dye sol...A series of chitosan-g-poly （acrylic acid）/vermiculite hydrogel composites were synthesized and used as adsorbents for the investigation of the effect of process parameters such as vermiculite content, pH of dye solution, contact time, initial concentration of dye solution, temperature, ionic strength and concentration of surfactant sodium dodecyl sulfate on the removal of Methylene Blue （MB） from aqueous solution. The results showed that the adsorption capacity for dye increased with increasing pH, contact time and initial dye concentration, but decreased with increasing temperature, ionic strength and sodium dodecyl sulfate concentration in the present of the surfactant. The adsorption kinetics of MB onto the hydrogel composite followed pseudo second-order kinetics and the adsorption equilibrium data obeyed Langmuir isotherm. By introducing 10 wt.% vermiculite into chitosan-g-poly （acrylic acid） polymeric network, the obtaining hydrogel composite showed the highest adsorption capacity for MB, and then could be regarded as a potential adsorbent for cationic dye removal in a wastewater treatment process.展开更多
Poly(vinyl alcohol)(PVA)/hydroxyapatite(HA)composite hydrogel specimens were prepared with 15%PVA and 1%,2%,3%,4%and 5%HA by repeated freezing-thawing.The tests of static and dynamic mechanical properties were carried...Poly(vinyl alcohol)(PVA)/hydroxyapatite(HA)composite hydrogel specimens were prepared with 15%PVA and 1%,2%,3%,4%and 5%HA by repeated freezing-thawing.The tests of static and dynamic mechanical properties were carried out todiscuss the influence of different contents of HA and freezing-thawing cycles on the mechanical properties of PVA/HA compositehydrogel.The results of static mechanical tests showed that the PVA/HA composite hydrogel with 3%HA and ninefreezing-thawing cycles had excellent stress relaxation properties,higher relaxation ratio,lower stress equilibrium value andpresented better properties of creep and recovery.The results of dynamic mechanical test showed that the PVA/HA compositehydrogel with nine freezing-thawing cycles had higher storage modulus and loss modulus,so was the PVA/HA compositehydrogel with 3%HA.展开更多
Three-dimensional printing technologies exhibit tremendous potential in the advancing fields of tissue engineering and regenerative medicine due to the precise spatial control over depositing the biomaterial.Despite t...Three-dimensional printing technologies exhibit tremendous potential in the advancing fields of tissue engineering and regenerative medicine due to the precise spatial control over depositing the biomaterial.Despite their widespread utilization and numerous advantages,the development of suitable novel biomaterials for extrusion-based 3D printing of scaffolds that support cell attachment,proliferation,and vascularization remains a challenge.Multi-material composite hydrogels present incredible potential in this field.Thus,in this work,a multi-material composite hydrogel with a promising formulation of chitosan/gelatin functionalized with egg white was developed,which provides good printability and shape fidelity.In addition,a series of comparative analyses of different crosslinking agents and processes based on tripolyphosphate(TPP),genipin(GP),and glutaraldehyde(GTA)were investigated and compared to select the ideal crosslinking strategy to enhance the physicochemical and biological properties of the fabricated scaffolds.All of the results indicate that the composite hydrogel and the resulting scaffolds utilizing TPP crosslinking have great potential in tissue engineering,especially for supporting neo-vessel growth into the scaffold and promoting angiogenesis within engineered tissues.展开更多
Halloysite nanotube-composited thermo-responsive hydrogel system has been successfully developed for controlled drug release by copolymerization of N-isopropylacrylamide （NIPAM） with silane-modified halloysite nanot...Halloysite nanotube-composited thermo-responsive hydrogel system has been successfully developed for controlled drug release by copolymerization of N-isopropylacrylamide （NIPAM） with silane-modified halloysite nanotubes （HNT） through thermally initiated free-radical polymerization. With methylene blue as a model drug, thermo-responsive drug release results demonstrate that the drug release from the nanotubes in the composited hy-drogel can^be well controlled by manipulating the environmental temperature. When the hydrogel network is swol- len at temperature below the lower critical solution temperature （LCST）, drug releases steadily from lumens of the embedded nanotubes, whereas the drug release stops when hydrogel shrinks at temperature above the LCST. The release of model drug from the HNT-composited hydrogel matches well with its thermo-responsive volume phasetransition, and shows characteristics of well controlled release. The design strategy and release results of the pro- posed novel HNT-composited thermo-responsive hydrogel system provide valuable guidance for designing respon- s_i_ve nanocomposites for controlled-release of active agents.展开更多
Polyvinyl alcohol hydrogels have been used in wearable devices due to their good flexibility and biocompatibility.However,due to the low thermal conductivity(κ)of pure hydrogel,its further application in high power d...Polyvinyl alcohol hydrogels have been used in wearable devices due to their good flexibility and biocompatibility.However,due to the low thermal conductivity(κ)of pure hydrogel,its further application in high power devices is limited.To solve this problem,melamine sponge(MS)was used as the skeleton to wrap boron nitride nanosheets(BNNS)through repeated layering assembly,successfully preparing a three-dimensional(3D)boron nitride network(BNNS@MS),and PVA hydrogels were formed in the pores of the network.Due to the existence of the continuous phonon conduction network,the BNNS@MS/PVA exhibited an improvedκ.When the content of BNNS is about 6 wt.%,κof the hydrogel was increased to 1.12 W m^(-1)K^(-1),about two times higher than that of pure hydrogel.The solid heat conduction network and liquid convection network cooperate to achieve good thermal management ability.Combined with its high specific heat capacity,the composites have an important application prospect in the field of wearable flexible electronic thermal management.展开更多
With the rapid development of textile industry,a large amount of dye-contaminated effluents was produced and caused serious environmental problem.To remove the dye from effluents,adsorption materials have been applied...With the rapid development of textile industry,a large amount of dye-contaminated effluents was produced and caused serious environmental problem.To remove the dye from effluents,adsorption materials have been applied because of their relatively cheap,high efficiency,and easy handling.In this study,a novel composite hydrogel bead with unique multilayer flake structure was fabricated by alginate,acrylamide and attapulgite for dye adsorption.Acrylamide was grafted polymerization onto alginate to obtain alginate-g-poly(acrylamide).Then alginate-g-poly(acrylamide)was cross-linked by Ca2+ions in present of attapulgite to form composite hydrogel bead.Scanning electron microscopy(SEM)results show that the freeze dried composite hydrogel bead has multilayer flake structure incorporating attapulgite.Fourier transform infrared spectroscopy(FTIR)and Thermo-gravimetric analysis(TGA)results indicate that acrylamide has been successfully grafted polymerization on sodium alginate.Grafting polymerization of acrylamide onto sodium alginate obviously enhances the swelling of hydrogel bead.Incorporating of attapulgite into hydrogel bead effectively enhances the adsorption capacity to methylene blue and the maximum adsorption capacity is 155.7 mg g-1.Multilayer flake structure increases the adsorption area for methylene blue,but hinders the diffusion of methylene blue into the inner of composite hydrogel bead.High pH solution is beneficial to the adsorption.Pseudo-second order model and Fraundlinch model best describe the adsorption kinetic and isotherm,respectively.These results indicate that composite hydrogel bead is a promising adsorption material for dye-contaminated water treatment.展开更多
Composites offer the option of coupling the individual benefits of their constituents to achieve unique material properties,which can be of extra value in many tissue engineering applications.Strategies combining hydr...Composites offer the option of coupling the individual benefits of their constituents to achieve unique material properties,which can be of extra value in many tissue engineering applications.Strategies combining hydrogelswith fibre-based scaffolds can create tissue constructs with enhanced biological and structural functionality.However,developing efficient and scalable approaches to manufacture such composites is challenging.Here,we use a droplet-based bioprinting system called reactive jet impingement(ReJI)to integrate a cell-laden hydrogel with a microfibrous mesh.This system uses microvalves connected to different bioink reservoirs and directed to continuously jet bioink droplets at one another in mid-air,where the droplets react and form a hydrogel that lands on a microfibrous mesh.Cell–hydrogel–fibre composites are produced by embedding human dermal fibroblasts at two different concentrations(5×10^(6) and 30×10^(6) cells/mL)in a collagen–alginate–fibrin hydrogel matrix and bioprinted onto a fibre-based substrate.Our results show that both types of cell–hydrogel–microfibre composite maintain high cell viability and promote cell–cell and cell–biomaterial interactions.The lower fibroblast density triggers cell proliferation,whereas the higher fibroblast density facilitates faster cellular organisation and infiltration into the microfibres.Additionally,the fibrous component of the composite is characterised by high swelling properties and the quick release of calcium ions.The data indicate that the created composite constructs offer an efficient way to create highly functional tissue precursors for laminar tissue engineering,particularly for wound healing and skin tissue engineering applications.展开更多
基金support from the National Natural Science Foundation of China(Nos.U21A20394 and 52305314)the Beijing Natural Science Foundation(Nos.7252285 and L246001)the National Key Research and Development Program of China(No.2023YFB4605800)。
文摘Granular composite(GC)hydrogels have attracted considerable interest in biomedical applications due to their versatile printability and exceptional mechanical properties.However,the lack of comprehensive design guidelines has limited their optimal engineering,as the factors influencing their mechanical performance and printability remain largely unexamined.In this study,we developed GC hydrogels by integrating microgels with interstitial matrices of photocrosslinkable gelatin methacrylate(GelMA).We utilized confocal microscopy and nanoindentation analyses to investigate the spatial distribution and mechanical behavior of these hydrogels.Our findings indicate that the mechanical and rheological properties of GC hydrogels can be precisely tailored by adjusting the volume fraction and size of the microgels.Furthermore,hydrogen bonds were identified as significant contributors to compressive performance,although they had minimal effect on cyclic mechanical behavior.Compared to bulk GelMA hydrogels,GC hydrogels demonstrated enhanced printability and remarkable superelasticity.As a proof of concept,we illustrated their dual printability in embedded printing to create prosthetic liver models for preoperative planning.This study provides valuable insights into the design and optimization of GC hydrogels for advanced biomedical applications.
基金the Haihe Laboratory of Sustainable Chemical Transformations for financial support。
文摘Water can be used as oxidant in conjunction with metal particles to form metal-water propellant to increase the energy of propellant.For this application,water needs to be stored in form of solid and capable of becoming liquid when use.Stable and thixotropic hydrogel has good potential as water-retaining material and oxidant of metal-based propellant.In this study,we prepared organic/inorganic composite hydrogels by combining inorganic gellants hectorite and fumed silica with organic gellant agarose,respectively.The total content of the gellants can be reduced to less than 2%by adding agarose.The influence of agarose on water content,phase transition temperature,centrifugal stability and other basic physical properties of composite hydrogels were discussed.The results show that the composite hydrogels have better thixotropy and stability than pure inorganic hydrogels,and the gel-sol transformation can be realized by applying shear force or heating to the phase transition temperature.The composite hydrogels have good shear thinning ability and improved mechanical stability.Fumed silica/agarose hydrogels have better physical stability,while the thixotropy and shear thinning ability of hectorite/agarose hydrogels are better.
基金financial support from the National Natural Science Foundation of China (No. 61801525)the Guangdong Basic and Applied Basic Research Foundation (Nos. 2020A1515010693, 2021A1515110269)+1 种基金the Fundamental Research Funds for the Central Universities, Sun Yatsen University (No. 22lgqb17)the Independent Fund of the State Key Laboratory of Optoelectronic Materials and Technologies (Sun Yat-sen University) under grant No. OEMT-2022-ZRC-05。
文摘Growing health awareness triggers the public's concern about health problems. People want a timely and comprehensive picture of their condition without frequent trips to the hospital for costly and cumbersome general check-ups. The wearable technique provides a continuous measurement method for health monitoring by tracking a person's physiological data and analyzing it locally or remotely.During the health monitoring process,different kinds of sensors convert physiological signals into electrical or optical signals that can be recorded and transmitted, consequently playing a crucial role in wearable techniques. Wearable application scenarios usually require sensors to possess excellent flexibility and stretchability. Thus, designing flexible and stretchable sensors with reliable performance is the key to wearable technology. Smart composite hydrogels, which have tunable electrical properties, mechanical properties, biocompatibility, and multi-stimulus sensitivity, are one of the best sensitive materials for wearable health monitoring. This review summarizes the common synthetic and performance optimization strategies of smart composite hydrogels and focuses on the current application of smart composite hydrogels in the field of wearable health monitoring.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.RS-2023-00207746,RS-2023-00207983)a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute(KHIDI)funded by the Ministry of Health&Welfare,Republic of Korea(grant number:HI19C075300).
文摘Wound healing in cases of excessive inflammation poses a significant challenge due to compromised neovascularization.Here,we propose a multi-functional composite hydrogel engineered to overcome such conditions through recruitment and activation of macrophages with adapted degradation of the hydrogel.The composite hydrogel(G-TSrP)is created by combining gelatin methacryloyl(GelMA)and nanoparticles(TSrP)composed of tannic acid(TA)and Sr^(2+).These nanoparticles are prepared using a one-step mineralization process assisted by metal-phenolic network formation.G-TSrP exhibits the ability to eliminate reactive oxygen species and direct polarization of macrophages toward M2 phenotype.It has been observed that the liberation of TA and Sr^(2+)from G-TSrP actively facilitate the recruitment and up-regulation of the expression of extracellular matrix remodeling genes of macrophages,and thereby,coordinate in vivo adapted degradation of the G-TSrP.Most significantly,G-TSrP accelerates angiogenesis despite the TA’s inhibitory properties,which are counteracted by the released Sr^(2+).Moreover,G-TSrP enhances wound closure under inflammation and promotes normal tissue formation with strong vessel growth.Genetic analysis confirms macrophage-mediated wound healing by the composite hydrogel.Collectively,these findings pave the way for the development of biomaterials that promote wound healing by creating regenerative environment.
基金The authors gratefully acknowledge the support from the National Natural Science Foundation of China(No.52072191)Heilongjiang Provincial Natural Science Foundation of China(No.LH2020E126)the Fundamental Research Fund of Heilongjiang Provincial University(No.135509204).
文摘Three-dimensional graphene materials have been studied as typical supercapacitors electrode materials by virtue of their ultrahigh specific surface area and good ion transport capacity.However,improvement of the poor volumetric electrochemical performance of these graphene materials has been required although they have high gravimetric energy density.In this work,nanocellulose/nitrogen and fluorine co-doped graphene composite hydrogels(NC-NFGHs)were prepared through a convenient hydrothermal approach utilizing ammonium fluoride as the heteroatom source.Nanocellulose(NC)and high concentration of graphene oxide(GO)were utilized to adjust the structure of NC-NFGHs and increase their packing density.Subsequently,the aqueous symmetric supercapacitor based on NC-NFGH-80 exhibits remarkable gravimetric(286.6 F·g^(-1))and volumetric(421.3 F·cm^(-3))specific capacitance at 0.3 A·g^(-1),good rate performance,and remarkable cycle stability up to 10,000 cycles.Besides,the all-solid-state flexible symmetric supercapacitors(ASSC)fabricated by NC-NFGH-80 also delivered a large specific capacitance of 117.1 F·g^(-1)at 0.3 A·g^(-1)and long service life over 10,000 cycles at 10 A·g^(-1).This compact porous structure and heteroatom co-doped graphene material supply a favorable strategy for high-performance supercapacitors.
基金supported by the National Basic Research Program of China (973 Project,2011CB606202)
文摘The ability to create artificial thick tissues is a major tissue engineering problem, requiring the formation of a suitable vascular supply. In this work we examined the ability of inducing angiogenesis in a bioactive hydrogel. GYIGSRG （NH2-Gly-Tyr-Ile- Gly-Ser-Arg-Gly-COOH, GG） has been conjugated to sodium alginate （ALG） to synthesize a biological active biomaterial ALG-GG. The product was characterized by IH NMR, FT-IR and elemental analysis. A series of CaCO3/ALG-GG composite hydrogels were prepared by crosslinking ALG-GG with D-glucono-8-1actone/calcium carbonate （GDL/CaCO3） in different molar ratios. The mechanical strength and swelling ratio of the composite hydrogels were studied. The results revealed that both of them can be regulated under different preparation conditions. Then, CaCO3/ALG-GG composite hydrogel was im- planted in vivo to study the ability to induce angiogenesis. The results demonstrated that ALG-GG composited hydrogel can induce angiogenesis significantly compared with non-modified ALG group, and it may be valuable in the development of thick tissue engineering scaffold.
文摘In this study, the effect of silica/calcium phosphate (SiCaP) nanocomposite particles on the properties of a novel chitosan-based thermosensitive hydrogel system was examined. SiCaP nanocomposite powder was fabricated using a sol-gel method and then used to fabricate nanocomposite hydrogels (Ch- <em>β</em>/7.5SiCaP and Ch-<em>β</em>/15SiCaP) including chitosan and <em>β</em>-glycerophosphate (Ch-<em>β</em>) as a matrix. Results revealed that compared to the Ch-<em>β </em>hydrogel without SiCaP, the presence of SiCaP particles in nanocomposite hydrogels maintained pH stability during the sol-gel transition, accelerated the gelation and improved the stiffness of nanocomposite hydrogels. Gelation time at 37℃ was reduced approximately 75% and stiffness was increased approximately 115%. Both of these changes are attributed to chemical and physical interactions of the SiCaP bioactive particles with chitosan. Furthermore, compared to the Ch-<em>β</em> hydrogel, the presence of SiCaP in the Ch-<em>β</em>/7.5SiCaP nanocomposite hydrogel did not affect biocompatibility negatively, but improved osteoblastic cell differentiation. Our studies suggest that these nanocomposite hydrogels may offer an innovative approach to bone regeneration strategies.
文摘Corresponding author’s name was incorrectly written as“Dadang Guo”instead of“Dagang Guo”.The correct author name should be“Dagang Guo”.The authors would like to apologise for any inconvenience caused.
基金funded by the National Key R&D Program of China(2022YFC2405904)the National Natural Science Foundation of China(52272284,32225028)+1 种基金Joint Research Unit Plan of the Chinese Academy of Sciences(121631ZYLH20240014)the Science and Technology Commission of Shanghai Municipality(24520750100)。
文摘Dental pulp-dentin complex defects remain a major unresolved problem in oral medicines.Clinical therapeutic methods including root canal therapy and vital pulp therapy are both considered as conservative strategies,which are incapable of repairing the pulpdentin complex defects.Although biomaterial-based strategies show remarkable progress in antibacterial,anti-inflammatory,and pulp regeneration,the important modulatory effects of nerves within pulp cavity have been greatly overlooked,making it challenging to achieve functional pulp-dentin complex regeneration.In this study,we propose an injectable bioceramicscontaining composite hydrogel in combination of Li-Ca-Si(LCS)bioceramics and gelatin methacrylate matrix with photocrosslinking properties.Due to the sustained release of bioactive Li,Ca and Si ions from LCS,the composite hydrogels possess multiple functions of promoting the neurogenic differentiation of Schwann cells,odontogenic differentiation of dental pulp stem cells,and neurogenesis-odontogenesis couples in vitro.In addition,the in vivo results showed that LCS-containing composite hydrogel can significantly promote the pulp-dentin complex repair.More importantly,LCS bioceramics-containing composite hydrogel can induce the growth of nerve fibers,leading to the re-innervation of pulp tissues.Taken together,the study suggests that LCS bioceramics can induce the innervation of pulp-dentin complex repair,offering a referable strategy of designing multifunctional filling materials for functional periodontal tissue regeneration.
基金supported by grants from the Beijing Natural Science Foundation,China(No.7244431)the Postdoctoral Science Foundation of China(No.2022M710260)the National Natural Science Foundation of China(No.82202723).
文摘Meniscal injury,a prevalent and challenging medical condition,is characterized by poor self-healing potential and a complex microenvironment.Tissue engineering scaffolds,particularly those made of silk fibroin(SF)/hyaluronic acid methacryloyl(HAMA)and encapsulating Mg^(2+),are promising options for meniscal repair.However,the inflammatory response following implantation is a significant concern.In this study,we prepared a composite SF/HAMA-Mg hydrogel scaffold,evaluated its physical and chemical properties,and detected its fibrochondrogenic differentiation effect in vitro and the healing effect in a rabbit meniscus defect model in vivo.Our results showed that the scaffold differentiates pro-inflammatory M1 macrophages into anti-inflammatory M2 macrophages after implantation,thereby reducing inflammation and facilitating the growth and repair of meniscus tissue.Further,the composite scaffold provided a conducive milieu for cell proliferation,anticipatory differentiation,and generation of extracellular matrix.In summary,composite SF/HAMA-Mg scaffolds exhibit exceptional biocompatibility and anti-inflammatory properties,demonstrating superior potential for meniscal repair.
基金the Natural Science Basic Research Program of Shaanxi Province(No.2023-JC-YB-101)the Basic Science Research Program of Shaanxi Basic Sciences Institute(Chemistry,Biology)(No.22JHQ079)National Natural Science Foundation of China(No.82272150).
文摘Designing advanced hydrogels with controlled mechanical properties,drug delivery manner and multifunctional properties will be beneficial for biomedical applications.However,the further development of hydrogel is limited due to its poor mechanical property and structural diversity.Hydrogels combined with polymeric micelles to obtain micelle-hydrogel composites have been designed for synergistic enhancement of each original properties.Incorporation polymeric micelles into hydrogel networks can not only enhance the mechanical property of hydrogel,but also expand the functionality of hydrogel.Recent advances in polymeric micelle-hydrogel composites are herein reviewed with a focus on three typical micelle incorporation methods.In this review,we will also highlight some emerging biomedical applications in developing micelle-hydrogel composite with multiple functionalities.In addition,further development and application prospects of the micelle-hydrogels composites have also been addressed.
基金supported by the National Natural Science Foundation of China (No.20877077)the Project of Jiangsu Provincial Science and Technology Office (No.BE2008087)
文摘A series of chitosan-g-poly （acrylic acid）/vermiculite hydrogel composites were synthesized and used as adsorbents for the investigation of the effect of process parameters such as vermiculite content, pH of dye solution, contact time, initial concentration of dye solution, temperature, ionic strength and concentration of surfactant sodium dodecyl sulfate on the removal of Methylene Blue （MB） from aqueous solution. The results showed that the adsorption capacity for dye increased with increasing pH, contact time and initial dye concentration, but decreased with increasing temperature, ionic strength and sodium dodecyl sulfate concentration in the present of the surfactant. The adsorption kinetics of MB onto the hydrogel composite followed pseudo second-order kinetics and the adsorption equilibrium data obeyed Langmuir isotherm. By introducing 10 wt.% vermiculite into chitosan-g-poly （acrylic acid） polymeric network, the obtaining hydrogel composite showed the highest adsorption capacity for MB, and then could be regarded as a potential adsorbent for cationic dye removal in a wastewater treatment process.
基金supported by National Natural Science Foundation of China(Grant No.50875252)Program for New Century Excellent TaIents in University(Grant No.NCET-06-0479)Natural Science Foundation of Jiangsu Proyince(Grant No.BK2008005)
文摘Poly(vinyl alcohol)(PVA)/hydroxyapatite(HA)composite hydrogel specimens were prepared with 15%PVA and 1%,2%,3%,4%and 5%HA by repeated freezing-thawing.The tests of static and dynamic mechanical properties were carried out todiscuss the influence of different contents of HA and freezing-thawing cycles on the mechanical properties of PVA/HA compositehydrogel.The results of static mechanical tests showed that the PVA/HA composite hydrogel with 3%HA and ninefreezing-thawing cycles had excellent stress relaxation properties,higher relaxation ratio,lower stress equilibrium value andpresented better properties of creep and recovery.The results of dynamic mechanical test showed that the PVA/HA compositehydrogel with nine freezing-thawing cycles had higher storage modulus and loss modulus,so was the PVA/HA compositehydrogel with 3%HA.
基金The authors acknowledge the funding support from the National Natural Science Foundation of China(Nos.52175474 and 51775324)the China Scholarship Council(No.202006890054).
文摘Three-dimensional printing technologies exhibit tremendous potential in the advancing fields of tissue engineering and regenerative medicine due to the precise spatial control over depositing the biomaterial.Despite their widespread utilization and numerous advantages,the development of suitable novel biomaterials for extrusion-based 3D printing of scaffolds that support cell attachment,proliferation,and vascularization remains a challenge.Multi-material composite hydrogels present incredible potential in this field.Thus,in this work,a multi-material composite hydrogel with a promising formulation of chitosan/gelatin functionalized with egg white was developed,which provides good printability and shape fidelity.In addition,a series of comparative analyses of different crosslinking agents and processes based on tripolyphosphate(TPP),genipin(GP),and glutaraldehyde(GTA)were investigated and compared to select the ideal crosslinking strategy to enhance the physicochemical and biological properties of the fabricated scaffolds.All of the results indicate that the composite hydrogel and the resulting scaffolds utilizing TPP crosslinking have great potential in tissue engineering,especially for supporting neo-vessel growth into the scaffold and promoting angiogenesis within engineered tissues.
基金Supported by the National ]qatural Science Foundation of China （20906064）, the National Basic Research Program of China （2009CB623407）, the Program for Changjiang Scholars and Innovative Research Team in University （IRTl163）, and the Foundation for the Author of National Excellent Doctoral Dissertation of China （201163）.
文摘Halloysite nanotube-composited thermo-responsive hydrogel system has been successfully developed for controlled drug release by copolymerization of N-isopropylacrylamide （NIPAM） with silane-modified halloysite nanotubes （HNT） through thermally initiated free-radical polymerization. With methylene blue as a model drug, thermo-responsive drug release results demonstrate that the drug release from the nanotubes in the composited hy-drogel can^be well controlled by manipulating the environmental temperature. When the hydrogel network is swol- len at temperature below the lower critical solution temperature （LCST）, drug releases steadily from lumens of the embedded nanotubes, whereas the drug release stops when hydrogel shrinks at temperature above the LCST. The release of model drug from the HNT-composited hydrogel matches well with its thermo-responsive volume phasetransition, and shows characteristics of well controlled release. The design strategy and release results of the pro- posed novel HNT-composited thermo-responsive hydrogel system provide valuable guidance for designing respon- s_i_ve nanocomposites for controlled-release of active agents.
基金the National Natural Science Foundation of China(Nos.52173078,52130303,and 51803151)the Young Elite Scientists Sponsorship Program by CAST(No.2019QNRC001)。
文摘Polyvinyl alcohol hydrogels have been used in wearable devices due to their good flexibility and biocompatibility.However,due to the low thermal conductivity(κ)of pure hydrogel,its further application in high power devices is limited.To solve this problem,melamine sponge(MS)was used as the skeleton to wrap boron nitride nanosheets(BNNS)through repeated layering assembly,successfully preparing a three-dimensional(3D)boron nitride network(BNNS@MS),and PVA hydrogels were formed in the pores of the network.Due to the existence of the continuous phonon conduction network,the BNNS@MS/PVA exhibited an improvedκ.When the content of BNNS is about 6 wt.%,κof the hydrogel was increased to 1.12 W m^(-1)K^(-1),about two times higher than that of pure hydrogel.The solid heat conduction network and liquid convection network cooperate to achieve good thermal management ability.Combined with its high specific heat capacity,the composites have an important application prospect in the field of wearable flexible electronic thermal management.
基金for Doctors of Jinling Institute of Technology(Grant No.jit-b-201415)the Natural Science Foundation for Colleges and Universities of Jiangsu Province(Grant No.12KJD150006)for the financial support of this research.
文摘With the rapid development of textile industry,a large amount of dye-contaminated effluents was produced and caused serious environmental problem.To remove the dye from effluents,adsorption materials have been applied because of their relatively cheap,high efficiency,and easy handling.In this study,a novel composite hydrogel bead with unique multilayer flake structure was fabricated by alginate,acrylamide and attapulgite for dye adsorption.Acrylamide was grafted polymerization onto alginate to obtain alginate-g-poly(acrylamide).Then alginate-g-poly(acrylamide)was cross-linked by Ca2+ions in present of attapulgite to form composite hydrogel bead.Scanning electron microscopy(SEM)results show that the freeze dried composite hydrogel bead has multilayer flake structure incorporating attapulgite.Fourier transform infrared spectroscopy(FTIR)and Thermo-gravimetric analysis(TGA)results indicate that acrylamide has been successfully grafted polymerization on sodium alginate.Grafting polymerization of acrylamide onto sodium alginate obviously enhances the swelling of hydrogel bead.Incorporating of attapulgite into hydrogel bead effectively enhances the adsorption capacity to methylene blue and the maximum adsorption capacity is 155.7 mg g-1.Multilayer flake structure increases the adsorption area for methylene blue,but hinders the diffusion of methylene blue into the inner of composite hydrogel bead.High pH solution is beneficial to the adsorption.Pseudo-second order model and Fraundlinch model best describe the adsorption kinetic and isotherm,respectively.These results indicate that composite hydrogel bead is a promising adsorption material for dye-contaminated water treatment.
基金funded by the EPSRC Centre for Doctoral Training in Additive Manufacturing and 3D Printing (EP/L01534X/1)DePuy International Limited
文摘Composites offer the option of coupling the individual benefits of their constituents to achieve unique material properties,which can be of extra value in many tissue engineering applications.Strategies combining hydrogelswith fibre-based scaffolds can create tissue constructs with enhanced biological and structural functionality.However,developing efficient and scalable approaches to manufacture such composites is challenging.Here,we use a droplet-based bioprinting system called reactive jet impingement(ReJI)to integrate a cell-laden hydrogel with a microfibrous mesh.This system uses microvalves connected to different bioink reservoirs and directed to continuously jet bioink droplets at one another in mid-air,where the droplets react and form a hydrogel that lands on a microfibrous mesh.Cell–hydrogel–fibre composites are produced by embedding human dermal fibroblasts at two different concentrations(5×10^(6) and 30×10^(6) cells/mL)in a collagen–alginate–fibrin hydrogel matrix and bioprinted onto a fibre-based substrate.Our results show that both types of cell–hydrogel–microfibre composite maintain high cell viability and promote cell–cell and cell–biomaterial interactions.The lower fibroblast density triggers cell proliferation,whereas the higher fibroblast density facilitates faster cellular organisation and infiltration into the microfibres.Additionally,the fibrous component of the composite is characterised by high swelling properties and the quick release of calcium ions.The data indicate that the created composite constructs offer an efficient way to create highly functional tissue precursors for laminar tissue engineering,particularly for wound healing and skin tissue engineering applications.
